﻿#region Copyright and License Notice
// Copyright (C)2010-2012 - Rob Levine and other contributors
// http://configgen.codeplex.com
// 
// This file is part of ConfigGen.
// 
// ConfigGen is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// 
// ConfigGen is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// 
// You should have received a copy of the GNU General Public License and 
// the GNU Lesser General Public License along with ConfigGen.  
// If not, see <http://www.gnu.org/licenses/>.
#endregion

using System.Collections.Generic;
using ConfigGen.Core.ConfigurationSettings;

namespace ConfigGen.Core.SettingsLoader
{

    /// <summary>
    /// Combines settings collections with global defaults
    /// </summary>
    public class DefaultSettingsCombiner : IDefaultSettingsCombiner
    {
        /// <summary>
        /// Returns the results of combining default settings with an existing <see cref="MachinesConfigurationCollection"/>
        /// </summary>
        /// <param name="localSettings">The settings from the settings file</param>
        /// <param name="defaultSettings">THe default settings that will be used if not overriden by the localSettings</param>
        /// <returns>The results of the combination</returns>
        public MachinesConfigurationCollection Combine(MachinesConfigurationCollection localSettings, MachinesConfigurationCollection defaultSettings)
        {
            var resultSettings = new List<MachineConfigurationSettings>();
            foreach (var localMachine in localSettings.MachineConfigurationSettings)
            {
                var defaultMachineFound = false;
                var combinedSettings = new List<ConfigurationSetting>();
                foreach (var defaultMachine in defaultSettings.MachineConfigurationSettings)
                {
                    if (localMachine.MachineName != defaultMachine.MachineName)
                    {
                        continue;
                    }
                    defaultMachineFound = true;
                    //Now go through the defaultSettings and add these or thier local overrides 
                    foreach (var defaultSetting in defaultMachine.ConfigurationSettings)
                    {
                        var localTokenFound = false;
                        foreach (var localSetting in localMachine.ConfigurationSettings)
                        {
                            if (localSetting.Token != defaultSetting.Token) 
                                continue;
                            localTokenFound = true;
                            combinedSettings.Add(string.IsNullOrEmpty(localSetting.Value) ? defaultSetting : localSetting);
                            //combinedSettings.Add(defaultSetting);
                        }
                        if (!localTokenFound)
                        {
                            combinedSettings.Add(defaultSetting);
                        }
                    }
                    //Now go through the localsettings and add any that aren't in defaultSettings
                    foreach (var localSetting in localMachine.ConfigurationSettings)
                    {
                        var defaultTokenFound = false;
                        foreach (var defaultSetting in defaultMachine.ConfigurationSettings)
                        {
                            if (localSetting.Token != defaultSetting.Token)
                                continue;
                            defaultTokenFound = true;
                        }
                        if (!defaultTokenFound)
                        {
                            combinedSettings.Add(localSetting);
                        }
                    }
                }
                resultSettings.Add(defaultMachineFound ? new MachineConfigurationSettings(localMachine.MachineName, localMachine.ConfigFilePath, combinedSettings) : localMachine);
            }
            return new MachinesConfigurationCollection(resultSettings);
        }
    }
}